Structural component

ABSTRACT

A structural component for an aircraft, spacecraft or rocket has a ply of fiber reinforced polymer, a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer. A component for manufacturing such a structural component, a method for manufacturing a component of this type, a method for manufacturing a structural component and an aircraft or spacecraft with such a structural component are described.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S.application Ser. No. 15/471,795 filed Mar. 28, 2017, which claimspriority to European Patent Application EP 16 164 424.0 filed Apr. 8,2016, the entire disclosures of which are incorporated by referenceherein.

TECHNICAL FIELD

The present disclosure pertains to a structural component, in particularfor an aircraft, spacecraft or rocket. The disclosure herein furtherpertains to a component for manufacturing such a structural component, amethod for manufacturing a component of this type, a method formanufacturing a structural component and an aircraft or spacecraftcomprising such a structural component.

Although applicable to any kind of structure that should be protectedfrom lightning and/or electromagnetic pulse, the present disclosure andthe problem on which it is based will be explained in greater detailwith reference to the fuselage structure of an aircraft, spacecraft orrocket.

BACKGROUND

In fiber reinforced polymer or fiber reinforced plastic structuralparts, in particular carbon fiber reinforced plastic (CFRP) or glassfiber reinforced plastic (GFRP), additional lightning strike protectionand electromagnetic shielding measures are usually provided.

A known solution for lightning strike protection (LSP) of composites(CFRP and GFRP) airframe structures is a lightning strike protectionlayer in the form of expanded metallic, in most cases copper foils(ECF). Such expanded metallic/copper foils are generally placed on thetop of composite structures. This specific design of a lightning strikeprotection layer helps to dissipate the lightning strike energy over thesurface, e. g. of an airframe component. Since the electricalresistivity of expanded copper foils is significantly larger than thatof CFRP/GFRP laminate, the lightning current flows almost completelywithin the lightning strike protection layer not affecting directly thecomposite laminate of the composite structure.

Other solutions for lightning strike protection measures known by theapplicant are other metallic layers, such as woven wire fabrics,interwoven metallic wires, metal coatings, solid metal foils orconductive and ionisable paints.

In another concept of lightning strike protection measure, a componentuseful in aircraft and spacecraft vehicles, comprises a resin matrix inwhich carbon nanotubes are embedded for high conductivity of thecomponent, and an internal layer at which an external layer adjoins. Acarbon fiber material is embedded in the resin matrix, which forms theexternal layer of the component. The internal layer is made of a fibercomposite material.

Particularly in aerospace applications, the use of carbon nanotubes(CNT) due to their superior properties for multifunctional applicationsseems to be very promising. A review about the imminent prospects ofutilizing carbon nanotubes due to their superior mechanical, thermal,and electrical properties for multifunctional aircraft and spaceapplications can be found for example in Gohardani, O., et al.,“Potential and prospective implementation of carbon nanotubes on nextgeneration aircraft and space vehicles: A review of current and expectedapplications in aerospace sciences”, Progress in Aerospace Sciences, 70,42, 2014.

The usually used Polyacrylnitril (PAN)-derived carbon fibers in CFRPlaminates offer a sufficient high electrical and a reasonable thermalconductivity, but the epoxy matrix is from an electrical point of viewan excellent electrical isolator. In case of GFRP structures, the glassfibers are electrically non-conducting. Thus, the general procedure forLSP purposes is to improve the matrix properties, particularly theelectrical (and thermal) conductivity, and possibly to network thecarbon fibers both within and between the adjacent plies, e.g. usingcarbon allotropes like carbon nanotubes (CNT). Also, other carbonallotropes like carbon black, short carbon fibers (SCF) or grapheneplates may be used.

SUMMARY

In some embodiments, the disclosure herein provides:

-   -   A structural component, in particular for an aircraft,        spacecraft or rocket, comprising: a ply of fiber reinforced        polymer; a first carbon nanotube mat; and a metallic layer,        wherein the carbon nanotube mat and the metallic layer are        arranged on the ply of fiber reinforced polymer to form a hybrid        lightning strike protection layer.    -   A component for manufacturing a structural component according        to the disclosure herein, comprising: a ply comprising fiber        material; a metallic layer; and a first carbon nanotube mat,        wherein the first carbon nanotube mat and the metallic layer are        arranged on the ply.    -   A method for manufacturing a component according to the        disclosure herein, comprising: placing a metallic layer, in        particular an expanded copper foil, and a first carbon nanotube        mat on a ply comprising fiber material.    -   A method for manufacturing a structural component, in particular        a structural component according to the disclosure herein,        comprising:    -   curing the matrix of a component according to the disclosure        herein or manufactured according to a method for manufacturing a        component of the disclosure herein such that at least the first        carbon nanotube mat and the metallic component are embedded in        the cured matrix.    -   An aircraft, spacecraft or rocket comprising a structural        component according to the disclosure herein and/or manufactured        according to a method of the disclosure herein.

One idea of the present disclosure is to combine a metallic layer and acarbon nanotube mat (CNT-M) to form a hybrid lightning strike protection(LSP) layer. The hybrid lightning strike protection (LSP) layer alsoserves as electromagnetic shielding measure.

An LSP measure or LSP layer according to the disclosure herein has thesame or even a lower weight than a standard LSP measure/layer. Moreover,mechanical damage of CFRP/GFRP laminates protected by the LSP measureaccording to the disclosure herein is significantly reduced.

Since CNT-Ms have high electrical conductivity, they contribute toenhanced electrical conductivity in the hybrid lightning strikeprotection layer. Thus, thermo-mechanical damage of CFRP/GFRP structureis reduced in case of a lightning strike, because the hybrid LSP layercomprising the metallic layer and the CNT-M has lower electricalresistance than, e. g. a metal LSP layer. Therefore, the generated Jouleheat is reduced.

Additionally, the CNT-Ms have an outstanding thermal stability, sincethe melting temperature of CNTs is about 4000° C. and thus much higherthan, e. g. that of copper of about 1084° C. Accordingly, the CNT-M maysupport the metallic layer at very high temperature such that the hybridprotection layer is more thermally-stable than ECF alone andadditionally allows energy storage in the form of latent heat. Since theCNT-M reduce the magnitude of Joule heat generated by the lightningstrike currents and also have high thermal conductivity, they dissipatethe generated heat faster from the lightning strike areas.

In some embodiments, the CNT-M are electro-chemical compatible with CFRPand GFRP materials. They can be easily incorporated with compositestructures and are easily paintable. Thus, the CNT-M can replace theusual surfacing film layer and provides similar functionality integratedwith the LSP properties. Accordingly, the LSP measure according to oneof the ideas of the present disclosure has the same or even lower weightthan a standard LSP measure, in particular depending on the surfaceweight of the metallic layer used.

Additionally, the surface weight of a metallic layer, for example anECF, can be reduced with the hybrid design. Thus, the hybrid LSPmeasure/layer will have the same or even lower weight than standard LSPmeasures/layers, in particular compared to ECF only. However, still animproved electrical conductivity is provided with the hybrid LSP layeraccording to the disclosure herein.

Finally, since CNT-M are extremely thermally stable, less energy isavailable for an explosion of the LSP layer. Thus, according to one ofthe ideas of the present disclosure, mechanical damage of CFRP/GFRPcomposite structures from lightning is significantly reduced.Accordingly, lightning induced repair and maintenance cost aredecreased.

Already available manufacturing processes can be used for the presentdisclosure. Thus, complexity and cost of manufacturing are notincreased. Moreover, already available repair and maintenance processesfor lightning strike induced damage can be used as well. Accordingly,additional complexity and cost of manufacturing, repair and maintenanceof protected CFRP/GFRP structure are preserved.

To sum up, the hybrid LSP layer according to one of the ideas of thedisclosure herein provides for a combination of desired properties andeliminates drawbacks of its single components in a synergetic way.

Generally, the CNT-M can be placed either underneath or on the top ofthe metallic layer. Furthermore, it is possible to sandwich the metalliclayer between two CNT-Ms.

The metallic layer may comprise any industrial metal or metal alloy withsufficiently high conductivity, e. g. comprising copper, nickel,aluminum, brass, bronze, or the like. For special applications, themetallic layer may comprise a metal or metal alloy with highconductivity comprising precious metal, such as e. g. silver.

The method of some embodiments of the present disclosure is variableregarding sequence of its steps. In particular, the step of impregnatingmay be conducted before or after the step of placement. Furthermore,infiltration or impregnation of the ply and the carbon nanotube mat maybe conducted together in one step or separately. In particular, it ispossible to use a readily cured ply of fiber reinforced polymer as plycomprising fiber material and firmly bond the carbon nanotube mat andmetallic layer thereto by way of curing a matrix of the carbon nanotubemat.

The method of manufacturing a structural component may involve all stepsof the method of manufacturing a component for manufacturing astructural component.

Manufacturing a structural component or a (non-cured or not completelycured) component for manufacturing the structural component may berealized by various molding processes, such as among others e. g.Pre-preg, Preforming, RTM (Resin Transfer Molding), Liquid CompressionMolding, SMC (Sheet Moulding Compound), RIM (Reaction InjectionMolding), BMC (Bulk Molding Compound), Extrusion Compression Molding,Structural Reaction Injection Molding, CFRTP (Carbon Fiber ReinforcedThermoPlastic) or the like.

A component for manufacturing the structural component may be providedas a semi-finished product in various configurations suitable for therespective molding process, e. g. as a preform or as a prepreg.

After curing, the metallic layer is embedded in the cured matrix on theCNT-M or between two CNT-Ms or between the CNT-M and the ply comprisingfiber material.

According to an embodiment of the structural component, the first carbonnanotube mat and the metallic layer are embedded in a matrix. Forexample, the matrix is a cured polymer resin. In particular the matrixof the ply of fiber reinforced polymer is the matrix in which the firstcarbon nanotube mat and the metallic layer are embedded. In this case,accordingly, the matrix embeds at least the fibers of the fibermaterial, the metallic layer and the first carbon nanotube mat. In thisway, an integrated design of the structural component with the LSPmeasure/layer is provided.

According to a further embodiment of the structural component oraccording to an embodiment of the component for manufacturing thestructural component, the hybrid lightning strike protection layercomprises a second carbon nanotube mat. In this case, the metallic layeris arranged between the first carbon nanotube mat and the second carbonnanotube mat. Accordingly, the metallic layer is sandwiched between thefirst and second CNT-M. In this way, improved thermal stability isachieved, since the CNT-Ms structurally support the metallic layer fromboth sides under very high temperature conditions.

According to a further embodiment of the structural component, the firstcarbon nanotube mat is arranged on the ply of fiber reinforced polymer.Accordingly, the first carbon nanotube mat is arranged on the plycomprising fiber material in an embodiment of a component formanufacturing the structural component. Thus, the metallic layer isarranged on the first carbon nanotube mat. In case a second carbonnanotube mat is provided, the metallic layer is for example arrangedbetween the first and second carbon nanotube mats. Alternatively or inaddition, a dielectric coating or paint can be arranged on the secondcarbon nanotube mat. In this way, the CNT-M can replace conventionalsurfacing film layers and thus offers the same functionality as thesurfacing film layer plus its LSP function in an integral way.Furthermore, a conventional veil can be omitted. Therefore, the hybridLSP layer advantageously has low weight, in particular lower weightcompared to conventional LSP measures.

According to an embodiment of the component for manufacturing thestructural component, at least the first carbon nanotube mat isimpregnated with a non-cured matrix. For example, the component isconfigured as a prepreg component. Other parts of the component may alsobe impregnated. In an embodiment, also the ply comprising fiber materialand/or a second carbon nanotube mat is impregnated with the non-curedmatrix. In this way, a pre-product or semi-finished product, inparticular a prepreg or preform, is provided which, in particularindependently, allows finishing the manufacturing of a structuralcomponent by curing.

According to a further embodiment of the structural component oraccording to an embodiment of the component for manufacturing thestructural component, the metallic layer comprises copper. In this way,the properties of the CNT-M are ideally added with the high conductivityof copper to advantageously provide for minimum effective electricalresistance. Optionally or in addition, the metallic layer is configuredas an expanded metallic foil. In this way, a low surface weight and highextensive expansion of the metallic layer is provided. In anotherembodiment, the metallic layer comprises or is configured as an expandedcopper foil.

According to a further embodiment of the structural component oraccording to an embodiment of the component for manufacturing thestructural component, the first carbon nanotube mat is configured asnon-woven carbon nanotube mat. Additionally, also the second carbonnanotube mat may be configured as non-woven carbon nanotube mat.Non-woven carbon nanotube mats provide for a large size, are easy tohandle and flexible. Furthermore, the CNTs don't need to be dispersed.In particular, the CNT-M is made of 100% CNTs, meaning pure CNT fabric.Thus it easily and cost-effectively can be impregnated with a resinusing custom industrial techniques. Since the non-woven CNTs in the mathave a high aspect ratio (˜1:100,000), improved electrical, thermal andmechanical properties are provided.

According to an embodiment of the method for manufacturing a component,the method further comprises a step of impregnating at least the firstcarbon nanotube mat with a non-cured matrix. In this way, the componentcan be manufactured as a prepreg component. Other parts of the componentmay also be impregnated simultaneously or in sequence. In an embodiment,also the ply comprising fiber material and/or a second carbon nanotubemat is impregnated with the non-cured matrix. In this way, a pre-productor semi-finished product, in particular a prepreg, is manufacturedwhich, in particular independently, allows finishing the manufacturingof a structural component by curing.

According to an embodiment of the method for manufacturing a componentor according to an embodiment of the method for manufacturing astructural component, the first carbon nanotube mat, the metallic layerand the ply are impregnated with the matrix together. In this way, anintegrated manufacturing process, in particular with only oneimpregnation step, is provided.

Furthermore, according to an embodiment of the method for manufacturinga structural component, the first carbon nanotube mat, the metalliclayer and the ply are embedded together in the cured matrix. In thisway, an LSP layer for a structural component can be manufactured in anintegrated and labor-saving process with conventional tooling.Accordingly, manufacture is possible with low complexity and thus at lowcost.

According to an embodiment of manufacturing the component or accordingto an embodiment of the method for manufacturing a structural component,placing the metallic layer and the first carbon nanotube mat on the plycomprises the steps of placing the first carbon nanotube mat on the ply;placing the metallic layer on the first carbon nanotube mat; and placinga second carbon nanotube mat on the metallic layer. In this way, anLSP-layer with double CNT-M enclosing the metallic layer, for example anECF, is provided. In this way, the hybrid LSP layer is provided withimproved thermal stability.

According to yet another embodiment of the method of manufacturing theprepreg component or according to an embodiment of the method formanufacturing a structural component, the method further comprises thestep of coating the second carbon nanotube mat with a dielectric coatingor paint. In particular, the coating or paint is applied directly on thesecond carbon nanotube mat. In this way, advantageously, a conventionalsurfacing film and/or a conventional veil can be omitted. The dielectriccoating or paint may be applied before or after curing of the matrix.

According to an embodiment of an aircraft or spacecraft, the structuralcomponent forms part of a skin of the aircraft or spacecraft. In thisway, advantageously, an effective lightning strike protection (LSP)measure is provided in the aircraft or spacecraft.

The above embodiments may be combined in any reasonable way. Inparticular, features of the prepreg component are applicable to thestructural component and vice versa. Furthermore, features of the methodfor manufacturing a prepreg component are applicable to the method formanufacturing the structural component and vice versa.

The disclosure herein will be explained in greater detail with referenceto exemplary embodiments depicted in the drawings as appended.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the present disclosure and are incorporated in andconstitute a part of this specification. The drawings illustrate theembodiments of the present disclosure and together with the descriptionserve to explain the principles of the disclosure herein. Otherembodiments of the present disclosure and many of the intendedadvantages of the present disclosure will be readily appreciated as theybecome better understood by reference to the following detaileddescription. The elements of the drawings are not necessarily to scalerelative to each other. In the figures, like reference numerals denotelike or functionally like components, unless indicated otherwise.

It will be appreciated that common and/or well understood elements thatmay be useful or necessary in a commercially feasible embodiment are notnecessarily depicted in order to facilitate a more abstracted view ofthe embodiments. It will further be appreciated that certain actionsand/or steps in an embodiment of a method may be described or depictedin a particular order of occurrences while those skilled in the art willunderstand that such specificity with respect to sequence is notactually required. It will also be understood that the terms andexpressions used in the present specification have the ordinary meaningas is accorded to such terms and expressions with respect to theircorresponding respective areas of inquiry and study, except wherespecific meanings have otherwise been set forth herein.

FIG. 1 schematically illustrates an exemplary sectional view oflightning strike protection measures of an airframe component.

FIG. 2 shows a schematic sectional view of a structural component.

FIG. 3 shows a schematic sectional view of a prepreg component.

FIG. 4 shows a front view of an exemplary aircraft.

Although specific embodiments are illustrated and described herein, itwill be appreciated by those of ordinary skill in the art that a varietyof alternate and/or equivalent implementations may be substituted forthe specific embodiments shown and described without departing from thescope of the present disclosure. Generally, this application is intendedto cover any adaptations or variations of the specific embodimentsdiscussed herein.

DETAILED DESCRIPTION

FIG. 1 schematically illustrates a sectional view of lightning strikeprotection of an airframe component.

In FIG. 1, reference sign 102 denotes a lightning strike protectionlayer placed on the top of a composite structure 100. The lightningstrike protection layer 102 comprises e.g. an expanded copper foil 101placed on the top of the composite laminate 103 but underneathprotective dielectric coatings (e.g. paint layers) 104.

A veil 105 (combined with an epoxy resin surfacing film) is placed onthe top of ECF 101 in order to decrease the surface roughness and toprepare the surface for the final varnish that is for example made up ofseveral layers, as shown in FIG. 1.

FIG. 2 shows a schematic sectional view of a structural component 1.

The structural component 1 comprises a ply 2 of fiber reinforced polymermaterial, which comprises a matrix 8 and a plurality of carbon fibers 9.The structural component e. g. forms a carbon fiber reinforced polymeror carbon fiber reinforced plastic (CFRP) fuselage component of the skin11 of an aircraft 10. The ply 2 of fiber reinforced polymer materialthereby forms the structural basis of the structural component 1.

It is to be understood that FIG. 2 schematically shows the arrangementof layers of the structural component at an outer side, which may formthe outer skin of an aircraft at any section thereof.

On the outer side of the ply 2 of fiber reinforced polymer, a hybridlightning strike protection (LSP) layer 5 is arranged. The hybrid LSPlayer 5 comprises first and second non-woven carbon nanotube mats(CNT-M) 3, 6 and a metallic layer 4 configured as expanded copper foil(ECF).

Carbon nanotubes (CNT) generally are cylindrical shaped carbon formswith nanometric diameters. In particular, they have a hollow structurewith walls made of graphite or of graphene (a hexagonal structure madeof carbon atoms).

Non-woven carbon nanotube mats (CNT-M) can be manufactured e. g. by wayof a gas-phase catalytic reaction creating a dense cloud of very longcarbon nanotubes. These can be collected, for example spun around adrum, to create a non-woven mat. Such non-woven carbon nanotube mats aremanufactured e.g. by Tortech Nano fibers Ltd., Israel or NanocompTechnologies Inc., USA.

An expanded copper foil (ECF) may be made from a continuous expansion ofcopper, e. g. by rolling. It can be provided with different surfaceweights, depending on the number and thickness of CNT-M in the hybridlightning strike protection layer 5.

In the embodiment of FIG. 2, the first CNT-M 3 is arranged on the ply 2of CFRP. Furthermore, a metallic layer 4 and a second carbon nanotubemat 6 are arranged on the first carbon nanotube mat 3. Accordingly, themetallic layer 4 is sandwiched between the first and second carbonnanotube mats 3, 6.

The first and second carbon nanotube mats 3, 6 and the metallic layer 4there between are completely embedded in the cured matrix 8 of the ply 2of fiber reinforced polymer material. Therefore, the hybrid LSP layer isfirmly bonded to the CFRP-ply 2 in an integrated way.

Additionally, the structural component 1 is covered with a dielectriccoating 7, which is arranged directly on the outer side of the secondcarbon nanotube mat 6.

FIG. 3 shows a sectional view of a prepreg component.

The prepreg component is a component 1′ for manufacturing a structuralcomponent 1 according to FIG. 2 by curing. Therefore, the prepregcomponent 1′ comprises a ply 2′ comprising a fiber material. The firstcarbon nanotube mat 3, the metallic layer 4 and the second carbonnanotube mat 6 are arranged on the ply in the order as described withreference to FIG. 2. However, the dielectric layer is not yet applied.

The ply 2′, the first carbon nanotube mat 3, the metallic layer 4 andthe second carbon nanotube mat 6 are impregnated with a non-cured matrix8′.

For manufacturing the prepreg component, the first carbon nanotube mat 3is placed on the ply 2′. Further, the metallic layer 4 is placed on thefirst carbon nanotube mat 3 and the second carbon nanotube mat 6 isplaced on the metallic layer 4. The complete component is thenimpregnated with a non-cured matrix 8′, which is e. g. aduroplastic/thermoset resin. This means, the ply 2′, the first carbonnanotube mat 3, the metallic layer 4 and the second carbon nanotube mat6 are all impregnated with the non-cured matrix 8′ together to form theprepreg component 1′.

For manufacturing a structural component 1 according to FIG. 2, thematrix 8′ of the prepreg component 1′ is cured such that the plycomprising fiber material, the first carbon nanotube mat 3, the metalliccomponent 4 and the second carbon nanotube mat are embedded in the curedmatrix 8 and thus firmly bonded with each other.

Finally, the outer side of the second carbon nanotube mat 6 is coatedwith a dielectric coating 7.

FIG. 4 shows a front view of an exemplary aircraft 10. The aircraft 10comprises a skin 11, part of which is formed as a structural component 1according FIG. 2.

Accordingly, the aircraft (10) comprises a hybrid lightning strikeprotection (LSP) measure comprising an expanded copper foil (ECF) and aCNT non-woven mat (CNT-M).

Although specific embodiments of the disclosure herein are illustratedand described herein, it will be appreciated by those of ordinary skillin the art that a variety of alternate and/or equivalent implementationsexist. It should be appreciated that the exemplary embodiment orexemplary embodiments are examples only and are not intended to limitthe scope, applicability, or configuration in any way. Rather, theforegoing summary and detailed description will provide those skilled inthe art with a convenient road map for implementing at least oneexemplary embodiment, it being understood that various changes may bemade in the function and arrangement of elements described in anexemplary embodiment without departing from the scope as set forth inthe appended claims and their legal equivalents. Generally, thisapplication is intended to cover any adaptations or variations of thespecific embodiments discussed herein.

For example, it is not ultimately necessary to provide a second CNTnon-woven mat. The hybrid lightning strike protection layer generallymay also work with one CNT-M only, depending on the layout thereof.Accordingly, the CNT-M or even a plurality of CNT-M can be placed eitherunderneath or on top of the metallic layer or ECF.

Additionally, the metallic layer does not necessarily have to consist ofor comprise an ECF, but may have either alternative or additional otherelements. In particular, the disclosure herein also covers other metalsor alloys, e. g. nickel, aluminum, iron, brass, bronze or the like. Forspecial applications, the metallic layer may comprise a metal or metalalloy with high conductivity comprising precious metal, such as e. g.silver. Furthermore, other kinds of layers then an expanded foil, e.g.an electrolytic foil, a grid (e. g. a wire grid or a stamped grid), orthe like may be used.

Furthermore, the method for manufacturing the component or thestructural component does not necessarily have to comprise a step ofimpregnation of the ply comprising fiber material. The ply may also beprovided as already cured ply, e. g. of CFRP or GFRP, and only thehybrid lightning strike protection layer, meaning at least the firstCNT-M and the metallic layer, are firmly bonded thereto, e. g. byimpregnation and curing.

It will also be appreciated that in this document the terms “comprise”,“comprising”, “include”, “including”, “contain”, “containing”, “have”,“having”, and any variations thereof, are intended to be understood inan inclusive (i.e. non-exclusive) sense, such that the process, method,device, apparatus or system described herein is not limited to thosefeatures or parts or elements or steps recited but may include otherelements, features, parts or steps not expressly listed or inherent tosuch process, method, article, or apparatus. Furthermore, the terms “a”and “an” used herein are intended to be understood as meaning one ormore unless explicitly stated otherwise. Moreover, the terms “first”,“second”, “third”, etc. are used merely as labels, and are not intendedto impose numerical requirements on or to establish a certain ranking ofimportance of their objects.

While at least one exemplary embodiment of the present invention(s) isdisclosed herein, it should be understood that modifications,substitutions and alternatives may be apparent to one of ordinary skillin the art and can be made without departing from the scope of thisdisclosure. This disclosure is intended to cover any adaptations orvariations of the exemplary embodiment(s). Furthermore, characteristicsor steps which have been described may also be used in combination withother characteristics or steps and in any order unless the disclosure orcontext suggests otherwise. This disclosure hereby incorporates byreference the complete disclosure of any patent or application fromwhich it claims benefit or priority.

1. A structural component for an aircraft, spacecraft or rocket,comprising: a ply of fiber reinforced polymer; a non-woven carbonnanotube mat; and a metallic layer, wherein the non-woven carbonnanotube mat and the metallic layer are arranged on the ply of fiberreinforced polymer to form a hybrid lightning strike protection layer.2. The component of claim 1, wherein the non-woven carbon nanotube matand the metallic layer are embedded in a matrix.
 3. The component ofclaim 1, wherein the non-woven carbon nanotube mat and the metalliclayer are embedded in a matrix of the ply of fiber reinforced polymer.4. The component of claim 1, wherein the metallic layer comprisescopper.
 5. The component of claim 1, wherein the metallic layer isconfigured as an expanded metallic foil.
 6. The component of claim 1,wherein the metallic layer is configured as an expanded copper foil. 7.A component for manufacturing a structural component, having a hybridlightning strike protection layer, wherein the component comprises: aply comprising fiber material; a metallic layer; a non-woven carbonnanotube mat, wherein the non-woven carbon nanotube mat and the metalliclayer are arranged on the ply and are configured to be integratedtogether to form a hybrid lightning strike protection layer.
 8. Thecomponent of claim 7, wherein at least the non-woven carbon nanotube matis impregnated with a non-cured matrix.
 9. A method for manufacturing acomponent for manufacturing a structural component having a hybridlightning strike protection layer, comprising: providing a plycomprising fiber material; providing a non-woven carbon nanotube mat;providing a metallic layer, wherein the non-woven carbon nanotube matand the metallic layer are configured to be integrated together to forma hybrid lightning strike protection layer; and arranging the metalliclayer and the non-woven carbon nanotube mat on the ply comprising fibermaterial.
 10. The method of claim 9, wherein the metallic layer isconfigured as an expanded copper foil.
 11. The method of claim 9,further comprising a step of impregnating at least the non-woven carbonnanotube mat with a non-cured matrix.
 12. A method for manufacturing astructural component having a hybrid lightning strike protection layer,wherein the method comprises: providing a ply comprising fiber material;providing a metallic layer; providing a non-woven carbon nanotube mat,wherein at least the non-woven carbon nanotube mat is impregnated with anon-cured matrix; arranging the metallic layer and the non-woven carbonnanotube mat on the ply comprising fiber material; and curing the matrixsuch that at least the non-woven carbon nanotube mat and the metalliclayer are embedded in the cured matrix.
 13. The method of claim 12,wherein the metallic layer is configured as an expanded copper foil. 14.The method of claim 12, wherein the non-woven carbon nanotube mat, themetallic layer and the ply are impregnated with the matrix together. 15.The method of claim 12, wherein the non-woven carbon nanotube mat, themetallic layer and the ply are embedded together in the cured matrix.16. An aircraft, spacecraft or rocket comprising a structural componentcomprising: a ply of fiber reinforced polymer; a non-woven carbonnanotube mat; and a metallic layer, wherein the non-woven carbonnanotube mat and the metallic layer are arranged on the ply of fiberreinforced polymer to form a hybrid lightning strike protection layer.17. The component of claim 16, wherein the non-woven carbon nanotube matand the metallic layer are embedded in a matrix.
 18. The component ofclaim 16, wherein the non-woven carbon nanotube mat and the metalliclayer are embedded in the matrix of the ply of fiber reinforced polymer.19. The component of claim 16, wherein the metallic layer comprisescopper.
 20. The component of claim 16, wherein the metallic layer isconfigured as an expanded copper foil.